diff options
Diffstat (limited to 'src/mesa/main/rastpos.c')
-rw-r--r-- | src/mesa/main/rastpos.c | 441 |
1 files changed, 441 insertions, 0 deletions
diff --git a/src/mesa/main/rastpos.c b/src/mesa/main/rastpos.c index 54b2125a80f..b468219e688 100644 --- a/src/mesa/main/rastpos.c +++ b/src/mesa/main/rastpos.c @@ -36,6 +36,447 @@ #include "rastpos.h" #include "state.h" #include "main/dispatch.h" +#include "main/viewport.h" +#include "util/simple_list.h" + + + +/** + * Clip a point against the view volume. + * + * \param v vertex vector describing the point to clip. + * + * \return zero if outside view volume, or one if inside. + */ +static GLuint +viewclip_point_xy( const GLfloat v[] ) +{ + if ( v[0] > v[3] || v[0] < -v[3] + || v[1] > v[3] || v[1] < -v[3] ) { + return 0; + } + else { + return 1; + } +} + + +/** + * Clip a point against the far/near Z clipping planes. + * + * \param v vertex vector describing the point to clip. + * + * \return zero if outside view volume, or one if inside. + */ +static GLuint +viewclip_point_z( const GLfloat v[] ) +{ + if (v[2] > v[3] || v[2] < -v[3] ) { + return 0; + } + else { + return 1; + } +} + + +/** + * Clip a point against the user clipping planes. + * + * \param ctx GL context. + * \param v vertex vector describing the point to clip. + * + * \return zero if the point was clipped, or one otherwise. + */ +static GLuint +userclip_point( struct gl_context *ctx, const GLfloat v[] ) +{ + GLuint p; + + for (p = 0; p < ctx->Const.MaxClipPlanes; p++) { + if (ctx->Transform.ClipPlanesEnabled & (1 << p)) { + GLfloat dot = v[0] * ctx->Transform._ClipUserPlane[p][0] + + v[1] * ctx->Transform._ClipUserPlane[p][1] + + v[2] * ctx->Transform._ClipUserPlane[p][2] + + v[3] * ctx->Transform._ClipUserPlane[p][3]; + if (dot < 0.0F) { + return 0; + } + } + } + + return 1; +} + + +/** + * Compute lighting for the raster position. RGB modes computed. + * \param ctx the context + * \param vertex vertex location + * \param normal normal vector + * \param Rcolor returned color + * \param Rspec returned specular color (if separate specular enabled) + */ +static void +shade_rastpos(struct gl_context *ctx, + const GLfloat vertex[4], + const GLfloat normal[3], + GLfloat Rcolor[4], + GLfloat Rspec[4]) +{ + /*const*/ GLfloat (*base)[3] = ctx->Light._BaseColor; + const struct gl_light *light; + GLfloat diffuseColor[4], specularColor[4]; /* for RGB mode only */ + + COPY_3V(diffuseColor, base[0]); + diffuseColor[3] = CLAMP( + ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3], 0.0F, 1.0F ); + ASSIGN_4V(specularColor, 0.0, 0.0, 0.0, 1.0); + + foreach (light, &ctx->Light.EnabledList) { + GLfloat attenuation = 1.0; + GLfloat VP[3]; /* vector from vertex to light pos */ + GLfloat n_dot_VP; + GLfloat diffuseContrib[3], specularContrib[3]; + + if (!(light->_Flags & LIGHT_POSITIONAL)) { + /* light at infinity */ + COPY_3V(VP, light->_VP_inf_norm); + attenuation = light->_VP_inf_spot_attenuation; + } + else { + /* local/positional light */ + GLfloat d; + + /* VP = vector from vertex pos to light[i].pos */ + SUB_3V(VP, light->_Position, vertex); + /* d = length(VP) */ + d = (GLfloat) LEN_3FV( VP ); + if (d > 1.0e-6F) { + /* normalize VP */ + GLfloat invd = 1.0F / d; + SELF_SCALE_SCALAR_3V(VP, invd); + } + + /* atti */ + attenuation = 1.0F / (light->ConstantAttenuation + d * + (light->LinearAttenuation + d * + light->QuadraticAttenuation)); + + if (light->_Flags & LIGHT_SPOT) { + GLfloat PV_dot_dir = - DOT3(VP, light->_NormSpotDirection); + + if (PV_dot_dir<light->_CosCutoff) { + continue; + } + else { + GLfloat spot = powf(PV_dot_dir, light->SpotExponent); + attenuation *= spot; + } + } + } + + if (attenuation < 1e-3F) + continue; + + n_dot_VP = DOT3( normal, VP ); + + if (n_dot_VP < 0.0F) { + ACC_SCALE_SCALAR_3V(diffuseColor, attenuation, light->_MatAmbient[0]); + continue; + } + + /* Ambient + diffuse */ + COPY_3V(diffuseContrib, light->_MatAmbient[0]); + ACC_SCALE_SCALAR_3V(diffuseContrib, n_dot_VP, light->_MatDiffuse[0]); + + /* Specular */ + { + const GLfloat *h; + GLfloat n_dot_h; + + ASSIGN_3V(specularContrib, 0.0, 0.0, 0.0); + + if (ctx->Light.Model.LocalViewer) { + GLfloat v[3]; + COPY_3V(v, vertex); + NORMALIZE_3FV(v); + SUB_3V(VP, VP, v); + NORMALIZE_3FV(VP); + h = VP; + } + else if (light->_Flags & LIGHT_POSITIONAL) { + ACC_3V(VP, ctx->_EyeZDir); + NORMALIZE_3FV(VP); + h = VP; + } + else { + h = light->_h_inf_norm; + } + + n_dot_h = DOT3(normal, h); + + if (n_dot_h > 0.0F) { + GLfloat shine; + GLfloat spec_coef; + + shine = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_SHININESS][0]; + spec_coef = powf(n_dot_h, shine); + + if (spec_coef > 1.0e-10F) { + if (ctx->Light.Model.ColorControl==GL_SEPARATE_SPECULAR_COLOR) { + ACC_SCALE_SCALAR_3V( specularContrib, spec_coef, + light->_MatSpecular[0]); + } + else { + ACC_SCALE_SCALAR_3V( diffuseContrib, spec_coef, + light->_MatSpecular[0]); + } + } + } + } + + ACC_SCALE_SCALAR_3V( diffuseColor, attenuation, diffuseContrib ); + ACC_SCALE_SCALAR_3V( specularColor, attenuation, specularContrib ); + } + + Rcolor[0] = CLAMP(diffuseColor[0], 0.0F, 1.0F); + Rcolor[1] = CLAMP(diffuseColor[1], 0.0F, 1.0F); + Rcolor[2] = CLAMP(diffuseColor[2], 0.0F, 1.0F); + Rcolor[3] = CLAMP(diffuseColor[3], 0.0F, 1.0F); + Rspec[0] = CLAMP(specularColor[0], 0.0F, 1.0F); + Rspec[1] = CLAMP(specularColor[1], 0.0F, 1.0F); + Rspec[2] = CLAMP(specularColor[2], 0.0F, 1.0F); + Rspec[3] = CLAMP(specularColor[3], 0.0F, 1.0F); +} + + +/** + * Do texgen needed for glRasterPos. + * \param ctx rendering context + * \param vObj object-space vertex coordinate + * \param vEye eye-space vertex coordinate + * \param normal vertex normal + * \param unit texture unit number + * \param texcoord incoming texcoord and resulting texcoord + */ +static void +compute_texgen(struct gl_context *ctx, const GLfloat vObj[4], const GLfloat vEye[4], + const GLfloat normal[3], GLuint unit, GLfloat texcoord[4]) +{ + const struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit]; + + /* always compute sphere map terms, just in case */ + GLfloat u[3], two_nu, rx, ry, rz, m, mInv; + COPY_3V(u, vEye); + NORMALIZE_3FV(u); + two_nu = 2.0F * DOT3(normal, u); + rx = u[0] - normal[0] * two_nu; + ry = u[1] - normal[1] * two_nu; + rz = u[2] - normal[2] * two_nu; + m = rx * rx + ry * ry + (rz + 1.0F) * (rz + 1.0F); + if (m > 0.0F) + mInv = 0.5F * (1.0f / sqrtf(m)); + else + mInv = 0.0F; + + if (texUnit->TexGenEnabled & S_BIT) { + switch (texUnit->GenS.Mode) { + case GL_OBJECT_LINEAR: + texcoord[0] = DOT4(vObj, texUnit->GenS.ObjectPlane); + break; + case GL_EYE_LINEAR: + texcoord[0] = DOT4(vEye, texUnit->GenS.EyePlane); + break; + case GL_SPHERE_MAP: + texcoord[0] = rx * mInv + 0.5F; + break; + case GL_REFLECTION_MAP: + texcoord[0] = rx; + break; + case GL_NORMAL_MAP: + texcoord[0] = normal[0]; + break; + default: + _mesa_problem(ctx, "Bad S texgen in compute_texgen()"); + return; + } + } + + if (texUnit->TexGenEnabled & T_BIT) { + switch (texUnit->GenT.Mode) { + case GL_OBJECT_LINEAR: + texcoord[1] = DOT4(vObj, texUnit->GenT.ObjectPlane); + break; + case GL_EYE_LINEAR: + texcoord[1] = DOT4(vEye, texUnit->GenT.EyePlane); + break; + case GL_SPHERE_MAP: + texcoord[1] = ry * mInv + 0.5F; + break; + case GL_REFLECTION_MAP: + texcoord[1] = ry; + break; + case GL_NORMAL_MAP: + texcoord[1] = normal[1]; + break; + default: + _mesa_problem(ctx, "Bad T texgen in compute_texgen()"); + return; + } + } + + if (texUnit->TexGenEnabled & R_BIT) { + switch (texUnit->GenR.Mode) { + case GL_OBJECT_LINEAR: + texcoord[2] = DOT4(vObj, texUnit->GenR.ObjectPlane); + break; + case GL_EYE_LINEAR: + texcoord[2] = DOT4(vEye, texUnit->GenR.EyePlane); + break; + case GL_REFLECTION_MAP: + texcoord[2] = rz; + break; + case GL_NORMAL_MAP: + texcoord[2] = normal[2]; + break; + default: + _mesa_problem(ctx, "Bad R texgen in compute_texgen()"); + return; + } + } + + if (texUnit->TexGenEnabled & Q_BIT) { + switch (texUnit->GenQ.Mode) { + case GL_OBJECT_LINEAR: + texcoord[3] = DOT4(vObj, texUnit->GenQ.ObjectPlane); + break; + case GL_EYE_LINEAR: + texcoord[3] = DOT4(vEye, texUnit->GenQ.EyePlane); + break; + default: + _mesa_problem(ctx, "Bad Q texgen in compute_texgen()"); + return; + } + } +} + + +/** + * glRasterPos transformation. Typically called via ctx->Driver.RasterPos(). + * + * \param vObj vertex position in object space + */ +void +_mesa_RasterPos(struct gl_context *ctx, const GLfloat vObj[4]) +{ + if (ctx->VertexProgram._Enabled) { + /* XXX implement this */ + _mesa_problem(ctx, "Vertex programs not implemented for glRasterPos"); + return; + } + else { + GLfloat eye[4], clip[4], ndc[3], d; + GLfloat *norm, eyenorm[3]; + GLfloat *objnorm = ctx->Current.Attrib[VERT_ATTRIB_NORMAL]; + float scale[3], translate[3]; + + /* apply modelview matrix: eye = MV * obj */ + TRANSFORM_POINT( eye, ctx->ModelviewMatrixStack.Top->m, vObj ); + /* apply projection matrix: clip = Proj * eye */ + TRANSFORM_POINT( clip, ctx->ProjectionMatrixStack.Top->m, eye ); + + /* clip to view volume. */ + if (!ctx->Transform.DepthClamp) { + if (viewclip_point_z(clip) == 0) { + ctx->Current.RasterPosValid = GL_FALSE; + return; + } + } + if (!ctx->Transform.RasterPositionUnclipped) { + if (viewclip_point_xy(clip) == 0) { + ctx->Current.RasterPosValid = GL_FALSE; + return; + } + } + + /* clip to user clipping planes */ + if (ctx->Transform.ClipPlanesEnabled && !userclip_point(ctx, clip)) { + ctx->Current.RasterPosValid = GL_FALSE; + return; + } + + /* ndc = clip / W */ + d = (clip[3] == 0.0F) ? 1.0F : 1.0F / clip[3]; + ndc[0] = clip[0] * d; + ndc[1] = clip[1] * d; + ndc[2] = clip[2] * d; + /* wincoord = viewport_mapping(ndc) */ + _mesa_get_viewport_xform(ctx, 0, scale, translate); + ctx->Current.RasterPos[0] = ndc[0] * scale[0] + translate[0]; + ctx->Current.RasterPos[1] = ndc[1] * scale[1] + translate[1]; + ctx->Current.RasterPos[2] = ndc[2] * scale[2] + translate[2]; + ctx->Current.RasterPos[3] = clip[3]; + + if (ctx->Transform.DepthClamp) { + ctx->Current.RasterPos[3] = CLAMP(ctx->Current.RasterPos[3], + ctx->ViewportArray[0].Near, + ctx->ViewportArray[0].Far); + } + + /* compute raster distance */ + if (ctx->Fog.FogCoordinateSource == GL_FOG_COORDINATE_EXT) + ctx->Current.RasterDistance = ctx->Current.Attrib[VERT_ATTRIB_FOG][0]; + else + ctx->Current.RasterDistance = + sqrtf( eye[0]*eye[0] + eye[1]*eye[1] + eye[2]*eye[2] ); + + /* compute transformed normal vector (for lighting or texgen) */ + if (ctx->_NeedEyeCoords) { + const GLfloat *inv = ctx->ModelviewMatrixStack.Top->inv; + TRANSFORM_NORMAL( eyenorm, objnorm, inv ); + norm = eyenorm; + } + else { + norm = objnorm; + } + + /* update raster color */ + if (ctx->Light.Enabled) { + /* lighting */ + shade_rastpos( ctx, vObj, norm, + ctx->Current.RasterColor, + ctx->Current.RasterSecondaryColor ); + } + else { + /* use current color */ + COPY_4FV(ctx->Current.RasterColor, + ctx->Current.Attrib[VERT_ATTRIB_COLOR0]); + COPY_4FV(ctx->Current.RasterSecondaryColor, + ctx->Current.Attrib[VERT_ATTRIB_COLOR1]); + } + + /* texture coords */ + { + GLuint u; + for (u = 0; u < ctx->Const.MaxTextureCoordUnits; u++) { + GLfloat tc[4]; + COPY_4V(tc, ctx->Current.Attrib[VERT_ATTRIB_TEX0 + u]); + if (ctx->Texture.Unit[u].TexGenEnabled) { + compute_texgen(ctx, vObj, eye, norm, u, tc); + } + TRANSFORM_POINT(ctx->Current.RasterTexCoords[u], + ctx->TextureMatrixStack[u].Top->m, tc); + } + } + + ctx->Current.RasterPosValid = GL_TRUE; + } + + if (ctx->RenderMode == GL_SELECT) { + _mesa_update_hitflag( ctx, ctx->Current.RasterPos[2] ); + } +} /** |